CVE-2018-12363

Severity: high (CVSS 8.8 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 3.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2018-10-18 · updated 2026-06-17
Weakness: CWE-416

Description

A use-after-free vulnerability can occur when script uses mutation events to move DOM nodes between documents, resulting in the old document that held the node being freed but the node still having a pointer referencing it. This results in a potentially exploitable crash. This vulnerability affects Thunderbird < 60, Thunderbird < 52.9, Firefox ESR < 60.1, Firefox ESR < 52.9, and Firefox < 61.

Affected products

Canonical Ubuntu Linux: 14.04, 16.04, 17.10, 18.04
Debian Linux: 8.0, 9.0
Mozilla Firefox: before 61.0; from 53.0 before 60.1.0 — fixed in 60.1.0, 61.0
Mozilla Firefox ESR: before 52.9 — fixed in 52.9
Mozilla Thunderbird: before 52.9; from 52.9.1 before 60.0 — fixed in 52.9, 60.0
RedHat Enterprise Linux Desktop: 6.0, 7.0
RedHat Enterprise Linux Server: 6.0, 7.0
RedHat Enterprise Linux Server Aus: 7.6
RedHat Enterprise Linux Server Eus: 7.5, 7.6
RedHat Enterprise Linux Server Tus: 7.6
RedHat Enterprise Linux Workstation: 6.0, 7.0

How to fix

Upgrade to a fixed version: Mozilla Firefox 60.1.0, 61.0; Mozilla Firefox ESR 52.9; Mozilla Thunderbird 52.9, 60.0. Check the vendor advisory for mitigations.

References

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